The article shows that formalizing private property rights has a positive effect on the propensity to respect the property of others. We study a recent large-scale land tenure reform in West Africa which was the first of its kind to be implemented as a randomized control-trial. Results of a modified dictator game show that the formalization of private property rights reduced an individual's willingness to take from others' endowment. We used additional experimental measures and post-experimental survey data to rule out alternative explanations for the observed behavior that do not imply a change in preferences.